Oxalis tuberosa - Oca

Latin plant name Oxalis tuberosa Common plant name Oca Plant type Perennial herbaceous plant Size (meters) < 1m Distinguishing features The plant is not known in the wild, but populations of wild Oxalis species that bear smaller tubers are known from four areas of the central Andean region. Oca was introduced to Europe in 1830 as a competitor to the potato. Oca is cultivated primarily for its edible stem tuber, but the leaves and young shoots can be eaten as a green vegetable also. Andean communities have various methods to process and prepare tubers, and in Mexico oca is eaten raw with salt, lemon, and hot pepper. Oca is fairly high in oxalates, concentrated in the skin, and the bioavailability of oxalate appears to be similar to spinach. Oca is one of the important staple crops of the Andean highlands, due to its easy propagation, and tolerance for poor soil, high altitude and harsh climates. Oca needs a long growing season, and is day length dependent, forming tubers when the day length shortens in autumn (around March in the Andes). In addition, oca requires climates with average temperatures of approximately 10 to 12°C (range: 4°C to17°C) and average precipitation of 700 to 885 millimeters per year. In areas with harsh winter climates, early frosts may cut back the foliage before the tubers have a chance to form. In tropical areas where the days are unchanging in length, oca will not set a crop successfully.